


Finding A Cure

by ViolaMoon



Series: Marauders adventures [7]
Category: Harry Potter - J. K. Rowling
Genre: Betrayal, M/M, Medicine, Post-Apocalypse, Werewolves
Language: English
Status: Completed
Published: 2020-11-10
Updated: 2020-11-10
Packaged: 2021-03-08 23:48:36
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,954
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27485284
Author URL: https://archiveofourown.org/users/ViolaMoon/pseuds/ViolaMoon
Summary: Sirius is betrayed by Peter and this causes his work in curing Lycanthropy to be twisted and misused by the Death Eaters. The world ceases to exist as he knows it and worst of all, his beloved Remus is affected. Sirius must find a way to fix this for his love and for the world.
Relationships: Sirius Black/Remus Lupin
Series: Marauders adventures [7]
Series URL: https://archiveofourown.org/series/1452745
Kudos: 12





	Finding A Cure

**Author's Note:**

> This story was also written for the Semi Final Round of the Eighth Season of the Quidditch League Fanfiction Competition: It's The End of The World as We Know It
> 
> I'm writing as Chaser 3 for Pride of Portree.
> 
> Chaser 3 prompt: [Social Science Fiction] The social sciences are the overriding theme in this type of fiction; however, science and technology will usually play a central role in the structure of the extrapolated society. (Also known as Speculative Fiction)
> 
> These are the prompts I'm using as a chaser to score some extra points:
> 
> 1: (word) Collapse
> 
> 5: (Song) It's The End Of The World As We Know It (I am using the title as inspiration for the plot and dialogue)
> 
> 12: (Character) Sirius Black
> 
> I am also writing for the Hogwarts School of Witchcraft and Wizardry forum:
> 
> Assignment 8: Magical and Mundane Languages – Task #12: Trigedasleng – Write about a post-apocalyptic world
> 
> Disclaimer: I don't own any part of the world J.K. Rowling has created. It's all hers, from Diagon Alley to Hogwarts to all the people living there.
> 
> Thanks to my fantastic team for betaing! - Ash Juillet, Cupcakeyyy & VanillaAshes
> 
> A/N: Post-Apocalyptic!AU where Peter betrays Sirius and his efforts to cure Lycanthropy instead of the Potters. Creative liberties taken regarding when the wolfsbane potion was created.

"It's the end of the world as we know it," James said as he watched from the barriers of New Godric's Hollow. A wooden palisade blocked the remaining survivors from the outside world. A lawless place. Full of dangers, feral werewolves, and Death Eaters eager to destroy the last bastion of the Order of the Phoenix. Hogwarts had fallen, and Dumbledore was gone, so it was up to the rest of the Order to fight on.

Sirius sat behind him on a hard and cold wooden bench, his head in his hands. His shoulders were hunched as if the entire world sat upon them. "How did it end up like this…" he asked out loud. "I didn't mean for this to happen to him… to Remus… to anybody." His voice was barely above a whisper.

"Lord Voldemort did this to him, Sirius. Not you," James said, glancing over at him for a moment. "You are not to blame."

Two months earlier, they seemed to have been winning the war. The Order had been making great strides in their efforts and they had been _this close_ to capturing Lord Voldemort himself. Then reports of large numbers of werewolves in the Muggle population had started to come in, marking the start of what had been about to come.

At first, it had been presumed that it was a rogue werewolf converting Muggles, but the numbers didn't add up. It took far too long to discover what it really was.

Sirius had nightmares every night since Remus had caught the virus. He wished he could have done more to save his love.

"Why don't you get some rest, Sirius?" James suggested as he observed his best friend. He looked pale, his eyes had black rings around them, and his clothes hung off his body like rags. He hadn't eaten properly ever since it had happened. "We have that meeting tomorrow morning, and Kingsley wants us there."

Sirius nodded and rose without a word. His guilt weighed him down, and he couldn't even find it in himself to answer his friend. If only James knew what he had done. This was all his fault. He might never forgive him.

**Two months prior:**

Sirius was standing in the kitchen of the house he shared with Remus. It had been a quiet morning, and Sirius was about to set off to work. What he was doing was top secret; he couldn't even tell Remus what it was.

Just as he was about to put down his newspaper, the wireless radio behind him gave off an alarm. "Attention, Attention – this is an emergency broadcast brought to you by the Ministry of Magic – Please be advised that large numbers of Muggles have been transforming into werewolves without a bite and with no full moon. The Ministry strongly encourages the greater wizarding population to stay indoors at night and ward their property. The Department for Muggle Affairs is working closely with the Department for the Regulation and Control of Magical Creatures to find the source of this outbreak. We advise the population to stay calm and contact the Ministry if they witness anything suspicious." With that abrupt announcement, the radio went silent.

Sirius stood up at once. ' _That can't be…'_ he thought. ' _How… how did it get out of the lab?'_ His mind raced. He was sure he had warded the doors and used the most complex of security measures. He had to get to the bottom of this because if this turned out to be what he thought it to be, then this was his fault.

A crash from upstairs brought Sirius out of his thoughts, followed by a growl. He recognised it at once. It was Remus. But it wasn't the full moon! It wasn't even nighttime! Sirius transformed into his Animagus form at once and ran upstairs.

Sure enough, Moony was snarling at Sirius and slashing at everything in reach. He was understandably confused, and Sirius wanted to cry and scream. Why had this happened? Moony lunged for Sirius and knocked the wind out of him as Sirius hit the dresser. Moony wasn't usually this strong. Sirius would need James for this too if he wanted to calm the wolf down enough to figure out what to do. He couldn't do this alone, but how could he explain that he had done this to his lover?

Sirius bolted out of the room and out of the house as fast as his canine legs could carry him. He transformed back and quickly warded the house to prevent Remus from escaping. "I'm sorry, Remus… I did this to you… I'm so sorry."

Sirius needed to know why this had happened. He needed to get to his lab. Now. Remus and James would have to wait.

He reached the boundary of his hidden lab where he worked with one other, Peter. While Peter had not been the best student at school, he was an excellent lab assistant. He trusted Peter; Peter idolised Sirius, so he must know what had happened.

What Sirius hadn't expected was that his lab had been ransacked and, in the centre, stood Peter, hidden in shadows.

"Peter… What happened? The virus… How?" Sirius could barely get the words out. It was supposed to cure Lycanthropy, not spread it.

Peter chuckled. "What do you think?" Peter stepped forward, and his face came into view. A maniacal grin graced his lips, and Sirius could see pure darkness in his eyes.

"My master wanted it. For a much nobler purpose than 'saving your poor halfbreed lover,'" Peter continued, his face scrunched together in disgust. "With this, we will win the war and stop you muggle-lovers once and for all."

Sirius gritted his teeth and pointed his wand at his former colleague and friend. "Remus, a halfbreed?" Sirius fumed. "How dare you call him that… Your friend! He stood up for you all those years at Hogwarts, and _this_ is how you repay him?" Sirius advanced, wand solidly pointed at the traitor.

"He's strong, Sirius. He wanted to kill me. We… You are on the losing side, we can't win. Join me, Sirius, join the winning side." Peter jumped back, frightened, as Sirius advanced, his eyes shining with determination.

" _Stupefy_!" Sirius roared, and Peter fell to the ground, unconscious. Sirius forced himself to take a deep breath. _Stay calm_ , he thought, and with a wave of his wand, Sirius summoned ropes to bind his former friend. _Stay focussed._ He wanted to kill him. He wanted to make him suffer like he was making Remus suffer, but he had bigger problems to take care of.

Sirius began taking inventory of what was left of his laboratory. He needed an example of the virus; without it, he wouldn't be able to create a cure. With a flick of his wand, the room started to clear, removing the rubble and broken glass. Sirius searched and searched and even tried using a Summoning Charm, but to no avail.

It was gone.

**Present** :

"Glad you decided to grace us with your presence, Black," Kingsley Shacklebolt said. He stood at the end of a table, upon which was a large map of the UK. He saw James and Lily, Dumbledore, the Longbottoms and others who he hadn't bothered to learn their names.

"Sorry…" Sirius muttered, moving to stand next to James. He had had a horrible night, filled with the usual nightmares, and on top of everything else, he was nursing a massive headache. "Please continue."

"Okay. A status report," Kingsley said. With a swish of his wand, small figures appeared on the map. "Most of Voldemort's army is in London and the other major cities." With a flick of Kingsley's wand, the map zoomed in on London and the figures grouped in the different areas of the city. Sirius recognised the Ministry where the largest concentration of Death Eaters was, but it shocked him to see a force in Diagon Alley.

"Wait… Diagon Alley?" Sirius asked. "When did this happen?" Last he had heard, the rest of the Aurors not affiliated with the Order were holding Diagon Alley.

"Last night. They raided Gringotts and freed the Dragon." Gasps filled the room. As if the wildness of Britain wasn't dangerous enough with the feral werewolves. Now there was a dragon loose? Sirius shook his head. This would throw a spanner in his plans alright.

"What are we going to do about it?" Sirius asked the room. He watched as the members of the Order looked to one another, and he knew the answer already. They wouldn't be doing anything.

"Seriously?" he exclaimed. His heart pounded in his chest, and he had to reign himself back to stop the rage, the stress from emerging. He needed to get to Diagon Alley; he needed supplies so he could start fixing this situation. He realised now that he couldn't just sit by wallowing and blaming himself. He had a responsibility. He may not have spread the virus, but he had created it.

"Our last mission concerning saving Hogwarts' population had a lot of casualties," Kingsley said. "I don't need to remind you who we have lost. Until we have more information, we can't risk losing anyone else." Sirius swallowed. Albus Dumbledore had fallen that night.

"I know." He inspected the map. "But we can't allow them to take everything. Diagon Alley is our top source of supplies, not to mention Gringotts. If we take this away from them, it would be a major victory for our side." Sirius looked around the room and saw the defeated looks on his companions' faces. "I know this is tough and many of us have lost loved ones," Sirius said softly. "Believe me, I lost… I lost Remus." He took a deep, shaky breath. "But we can't give up!"

James stepped forward and placed a hand on his shoulder. "I know what you're going through, mate, but we have to take calculated risks. There are so many places a Death Eater can hide. It is a death trap, quite literally. We can't risk losing any more people," James urged. "I get it, and part of me wants to lead the charge. But I have Lily and Harry to think about. We need to wait for the right moment to strike, and this is not it."

Sirius wanted to argue with him, he needed to go. He wanted to remind James that Remus was out there and that he needed them. But he understood, no matter how much it hurt; Lily and Harry needed protecting, his priorities had changed. It was up to Sirius to save Remus, and he knew now that he had to venture out on his own if he was to ever fix the mess that he had put the world in.

It had been a long and mentally exhausting meeting. Once he was sure he was alone in the abandoned cottage on the outskirts of the settlement, Sirius spelled the door shut and started to prepare. First, he finished corking the potions he had been brewing. Luckily with the funk he was in, he had focused on his work and had created quite the storeroom full of potions for every situation imaginable. Then Sirius started packing a bag. He didn't need much food, some potions - mainly Essence of Dittany- and a variety of potion ingredients and a basic potions kit. He would need the kit to brew an antidote. He wasn't sure if it would be enough, but he had to try.

Just as he was about to leave, there was a knock at the door, followed by a, "Sirius mate, let me in." It was James and Sirius knew what he was here to do. He was here to stop him.

"No, James, I have to go, don't even try to talk me out of this," Sirius said through the door.

"Just give it time, Sirius. We will take Diagon Alley back, just not now. Why does it have to be now?"

"Because Remus is out there, James. What would you do if Lily was out there? If she was stuck as a werewolf?" Sirius said. James went silent for a moment before Sirius heard a sigh.

"I understand, and I know you well enough to know that I can't stop you, but please…" James urged. "Please be careful."

Sirius placed his hand on the door and smiled an uneasy smile. "I will. Kiss Lily and Harry for me."

"Bring Remus back, Sirius," James answered quietly. Sirius heard a soft thud, indicating that his friend had rested his head against the wood of the door. "But most importantly, come back safe and sound. I don't want to lose another friend."

Sirius nodded, knowing he couldn't promise anything. But James knew that just as well, as Sirius had felt the ward being lifted. Without wasting any more time, Sirius apparated a few streets away from the Leaky Cauldron.

The streets of London were surprisingly quiet, cars abandoned in various places; clear signs this location had been hit with the virus. Sirius kept to the shadows, wand at the ready.

He slipped into the Leaky Cauldron and found it thankfully empty. The Death Eaters had obviously not arranged a guard yet after their takeover the night before. Sirius only needed to get to the Apothecary. Then he could get to his lab.

Unlike the pub, Diagon Alley was busy, and Sirius had to work hard to avoid detection, therefore, stayed in his animagus form. He wasn't comfortable with this hide and seek style of travelling, but he couldn't risk getting caught.

A Death Eater turned around at the far end of the alleyway and Sirius realised that he was about to get caught. Sirius spotted a small opening between two buildings. He could just about squeeze through it. 'If I'm convincing enough, I'll fool him,' he thought. He barked at the Death Eater and then bolted over to the opening. 'Okay, I think I am safe now.'.

Finally, he made it to the mostly unguarded Apothecary shop to get the supplies he needed. . Scanning around quickly, he cast a notice-me-not charm on the doors and windows before grabbing all the ingredients he needed for a Wolfbane potion as well as a few other supplies; after all, he wasn't entirely sure what he needed, it was an experiment.

Once he had everything he needed, he slipped out the back, retracing his route in dog form to get to a safe apparition point. Now came the hard part: He _had_ to create a cure.

Sirius stepped back into his laboratory. He set about recreating the original virus. He had a good idea of how the Death Eaters had twisted it, and now he just needed to rework it. His main goal right now was to cure Remus or at least get him back to where he was before all this happened. He then combined this with wolfsbane. It had to work. Sirius needed Remus. He bit his lip nervously, holding the promising flask of potion in his hand. ' _Only one way to find out_ ,' he thought, and apparated back home.

"You can do it, Sirius," he muttered to himself as he stood at the boundary of his home. He gripped the potion bottle in one hand and wand in the other. He would need to stun Remus and then force it down the werewolf's throat. It was dangerous and extremely difficult, but it was the only way. If he got bit, it would be over.

He lowered the ward and stepped through. Vigilantly, he went from room to room and hoped that he could find Remus in a calm state, but a roar from the other room disproved this hope. Just then, Moony burst through the already splintered door and began advancing on Sirius, growling lowly and showing his sharp and poisonous teeth. He had seemed to have grown in the time Sirius had been away. How could that be possible?

"Easy, love. I am going to fix this."

Moony snarled at him and just as he was about to lunge, Sirius cried out, " _Stupefy maxima_!" It missed, and Sirius had to jump out of the way to avoid Moony's deadly claws.

He cast the spell again as Moony was recovering from the swing, and this one hit the massive werewolf directly in the chest, causing him to finally fall unconscious. After checking that Moony was in fact unconscious, Sirius approached and used his wand to magically pry the wolf's mouth open and pour the potion in. He massaged his throat to force him to swallow, and then he stepped away. Sirius ran as fast as he could out of the building. He didn't know how long the stunning curse would hold, so he placed the wards back up. Now all he could do was wait. He would have to watch from a safe distance away. This had to work. If it didn't… he wouldn't stop until he found something that did.

Just as the sun started to rise over his old home, Sirius was shaken awake.

"Sirius!" Remus said, shaking him again. "What happened to our house? What happened to _you_?"

Sirius bolted upright and pulled Remus into a giant hug. "You're okay! I can't believe it! It worked!" Sirius pulled away to examine him and then hugged Remus once more. "I will explain everything, but first, we need to get to James."

With that, the two apparated to New Godric's Hollow with quite the tale to tell and a batch of cures to brew. He had just discovered a cure for so many others - perhaps this would also aid in the war against he-who-must-not-be-named.


End file.
